Roller cutter mounting



Aug. 30, 1938.

A. C. CATLAND ET AL ROLLER CUTTER MOUNTING Filed Nov. 17, 1956 Patented Aug. 30, 1938' UNITED STATES ROLLER CUTTER. MOUNTING Alfred C. Catland, Alhambra,

and Philip C.'

Efromson, Whittier, Calif., assignors to Globe Oil ToolsCompany, Los Nietos, Calif., a corporation of California Application November 17, 1936, Serial No. 111,1 82

1o claims.

ball bearing mounting for a roller cutter in which all of the thrusts are transmitted through the balls and the races of the cutter bushing and pin so that the body of the drill is not subjectedto wear due to rotation of the cutter.

Another object of lthis invention is to provide anl anti-friction ball bearing mounting of the character mentioned that is small and v'ery compact andtherefore particularly adaptedior mounting a roller cutter of a. core drill.

Another object of the invention is to provide an anti-frictionK cutter mounting of the character mentioned that is long wearing to maintain the- Vcutter in the operative position for a long period of use'so that the cutter maintains the drill to gage.

Another object of the invention is to provide a cutter mounting of the character mentioned in which the end race or the thrust bushing is rigidly secured to the body of the drill, thereby preventing chattering of the bearing parts.

The various objects and features of our invention will be fully understood from the following detailed description of a typical preferred form and application of our invention, throughout which description reference is made to the accompanying drawing, in which:

Fig. l is a side elevation of a core drill embodying the present invention with a portion broken away to illustrate the cutters and their mountings in vertical cross-section. IElg.'2r is an enlarged fragmentary vertical sectional view illustrating one of the outer cutters and itsmounting. Fig. 3 is a view similar to Fig. 2 illustratingone of the inner cutters and its mounting 'and Fig. 4 is a fragmentary sectional view taken as indicated by line 4 4 on Fig. 2.

The cutter mountings o f -the pres-ent invention are adapted to be embodied in rock drills as well as rock core drills. Due to the fact that they are small and compact the mountings are particularly well adapted for embodiment in roller rock core drills. Accordingly, we will describe the cutter (Cl. Z55-72) mountings of the present invention embodied in a rock core drill, it being understood that the invention is not to be construed as limited to the specific form or application about to be described. The core drill illustrated in the'drawing includes an outer barrel I to be connected with a rotary well drill string. A tubular bithead I I is connected with the lower end of the barrel I0 through the medium of a sub I2. The head II has a central vertical opening I3 to pass the core. and an inner barrel I4 is provided within the outer barrel I0 to receive the core. Circumferentially spaced sockets or recesses I5 and I6 are provided in the lower end of the head I I to receive the roller cutters. The inner and outer walls I1 and I8 of the recesses I5 are inclined downwardly and out` wardly relative to the vertical axis of the tool. The inner and outer walls I9 and 20 of the recesses I6 are inclined downwardly and inwardly with respect to the vertical axis of the drill. Bearing surfaces 2i are provided on the o uter walls I8 of the recesses I5 and similar raised surfaces 22 are provided on the inner walls I9 of the recesses I6'. Fluid ports 23 and 24 are provided in the head Il to. communicate Withtheiupper ends ofSthe recessbs I5 and I6 respectively, to eiect the ilushing of the cutters. It is tobe understood that the head may have one or more'. cutterireceivlng recesses I5 and I6.

The present invention includes a cutter 25 for operation in each recess I5, fa pin 26 passing through the cutter 25, a washer or bushing 21 on the pin 26 and series of balls 2B and 29 cooperating y with races in the pin 26, the bushing 21 andthe cutter 25.

'I'he cutter 25 is a irusto-conical roller cutter intended tov rotate about a downwardly and inwardly inclined axis. The cutter 25 is -rotatably mounted in its recess I5 to act on the outer portion of the well b'ore and cut the bore to gage.4 'I'he pitched or conical periphery of the cutter 25 is provided with suitable cutting teeth 30. In the structure illustrated the teeth 30 are straight and axial. The outer corners of the teeth 30 are bevelled away to act on the vertical side wall of the well bore. The opposite ends of the cutter 25 may be ilat and normal to its axis. The cutter 25 is provided with a central longitudinal opening 3l to receive the pin 26 and the other bearing parts. The opening 3l is generally cylindrical and -is provided intermediate its ends with a restriction or flange 32. The inner side ofthe flange 32 is spherically concaved to constitute a ball race 33. The outer side of the ilange 32 is spherically concaved to form an outer ball race 34. The race 34.

. ing. The races 33 and 3d are positioned to face Astrainsfrom the washer to the head toward the adjacent ends o'f the cutter and diagonally relative to the longitudinal axis of the cutter.

The shaft or pin 26 passes through the opening 3| of the cutter 25 and is carried by the head il to rotatably support the cutter 26. The supporting pin 26 is passed outwardly through a downwardly and inwardly inclined opening 55 in the inner wall of the head Ii to extend outwardly through the recess I5 and the outer portion or the pin is threaded in a correspondingly inclined opening 3E in the outer wall portion of the head. A head 31 is provided on the inner end of the pin 26 and is suitably recessed in the inner end ofthe opening 35. A part of the head 31 is peened into a notch 33 to prevent unthreading of the pin. In accordance with the invention the pin 26 is graduated in diameter to have two outwardly facing annular shoulders 39 and 40. The shoulder 39 may be fiat and normal with respect tothe longitudinal axis of the pin. The inner shoulder 40 is in the nature of a ball race and is spherically concaved. The shoulder or race 4U is spaced slightly inwardly from the race 33 so that a line drawn through the centers of the opposing races 33 and 40 is pitched with respect to the longitudinal laxis of the pin 2&3.

The washer or bushing 21 surrounds the pin 26 and bears against the bearing surface 2| on the outer wall I8 ofthe recess I5. The inner end of the bushing 21 is engaged by the shoulder 33'.

which clamps the bushing against the surface 2i. In accordance with the invention a fiat sided key or rib 4| is provided on the surface 2| and is received in a correspondingly shaped groove 42 in the bushing 21 to prevent rotation of the bushing.

'The washer or bushing 21 may be welded to the head I I at the lower end of the surface 2| as indicated at 43 to positively hold the bushing against movement with respect to the head. The welding at 43 may also transmit some of the upward The y washer or bushing 21 is received in the outer portion of the cutter opening 3 I. A spherically concaved annular race 44 is provided in the inner end or corner of the bushing 21. 'I'he race 44 opposes the race 34 in the interior of the cutter 25 and is located so that a line drawn through the centers of the two races is pitched with respect to the longitudinal axis of the pin 26.

The series of balls 2l cooperates with the opposing races 33 and 40 and the series of balls 23 cooperates with the races 34 and 44 to rotatably support the roller cutter 25. The balls 28 and 29 are arranged in annular series to surround the pin 26 and the inner end portion of the washer 'or bushing 21. The outer series of balls 23 takes the principal end thrusts as well as some of the radial thrusts and therefore the balls 23 are larger in diameter than the balls 23. The races 33 and 40 are shaped and proportioned to properly cooperate with the balls 29 to rotatably support the inner end portion of the cutter 25, while the races 34 and 44 are formed and proportioned to cooperate with the balls 29 so that they rotatably support the outer end portion of the cutter. It will be observed that the series of balls 28 and 23 constitute the sole means for rotatably carrying or supporting the cutter 25. It is an important feature of the invention that the balls 28 assume the radial thrusts as well as the inward thrusts or thrusts toward the ^enter of the head while arcanos the balls 2@ assume the radial thrusts as well as the outward and the end thrusts.

Accordingly,

the two series of balls 2d and 2@ receive all of the f operating thrusts imposed on the cutter 25 relieving the head it of all wear due to rotation of the cutter. A washer l5 may be arranged between the inner end of the cutter 25 and the inner wail ill of the recess i5, spacing the cutter vfrom the inner wall of the recess. The washer 35 may be welded to the head ii at 55 to prevent it from turning.

it will be noted that the cutter 25 rotatably supported as just described may freely rotate during operation with a minimum ci friction. The bearing means mounting the cutter 26 is such that the cutter is prevented from shifting or wabbling and the cutter is definitely retained in position to cut the well bore to gage. The balls 23 and 2t which serve to rotatably support the cutter 25 on the pin 26 and thebushing 21 are very long wearing so that the cutter is rotatably supcutter do not bear on any parts of the head it or on the washer d5 for the transmission of the end thrusts. This, of course, relieves the head it ot excessive wear and greatly simpliiies the construction. The inner series of balls 26 cooperates 4 with the race M on the .pin 26, making the cutter mounting very compact. Being small and cornpact, the cutter mounting is particularly adapted tomounting the roller cutters of a core drill.

The cutter mounting of the present invention illustrated in Fig. 3 rotatably supports an inner cutter 50 in one of the recesses I6 of the drill head II. 'Ihe structure illustrated in Fig, 3 includes, generally, the cutter 50, a pin 5| passing through the cutter 50, a washer or bushing 52 on the pin 5I and series of balls 53 and 54 cooperating with the interior of the cutter 50 and with the pin -5| and the bushing 52 to rotatably support the cutter.

The cutter 5|I is an inner cutter for acting on the formation at the bottom of the well bore and for cutting the core tosize. The cutter 50 is substantially cylindrical and has at parallel ends. A central longitudinal opening 55 extends through the cutter 50 from one end to the other. Peripheral cutting teeth 56 are provided on the cutter 50. The teeth 56 may be straight andaxial and their ends or corners may be bevelled off as illustrated. A restriction or flange 51 is provided on the wall of the opening 55 between its ends. The outer side of the ange 51 is spherically concaved to form a ball race 53. The inner side of the flange 51 is spherically concaved in alike manner to constitute an annular ball race 53.` The cutter opening 55 is somewhat enlarged in diameter at its inner portion to receive the bushing 52. The ball races 58 and 59 provided on the sides of the flange 51 face inwardly toward the longitudinal center of-the cutter 50 and toward the adjacent ends of the cutter.

The pin 5| is similar, generally, to the abov described pin 26. The pin 5| is passed inwardly through a. downwardly and outwardlyjnclined opening 60 in the outer wall portion of the head and extends inwardly to pass through the opening 55 of the cutter 50. The inner part of the pin 5| is threaded in a downwardly and outwardly inclined opening 6| in the inner wall part of the head A suitable head 62 is provided on the outer end of the pin 5I and is recessed in the outer end of the opening B0. The head 52 f may have a part peened over into a notch t2* in the exterior of the drill head 'vll to prevent unthreadingof the pin Il. ,In accordance with the invention the pin 5l is graduated in diameter to have two inwardly facing annular shoulders '63 and 6I. 'I'he shoulder- Il may be flat and normal to the axis of the pin 5l, while the shoulder` 64 is spherically concaved to constitute a ball bearing race. The race 4 opposes the race 5d .on the interior of the cutter I and is-spaced The washer or bushing 52 is arranged` on the pin l within the cutter 50 to engage against the bearing surface 22. The bushing 52 is provided with a groove 42a similar to the above described groove d2 to receive a key or rib 4i on the surface 22 which prevents rotation of the bushing. Welding t5 may secure the bushing E2 to the inner wall part of the head il to positively prevent movement of the bushing. spherically concaved ball race 68 is provided in the inner end of the bushing 52 to oppose the race 59 on the interior of the cutter Sii. The race St is located some distance inwardly from the race 59 so that a linedrawn through the centers of the two races is pitched or diagonal with respect to the longitudinal axis of the pin 5i.

The series of balls 53 and Ed cooperate with the pairs of opposed races 6d and M and t@ and tt. respectively to rotatably support the cutter Et. The balls 53 and 5t are arranged in annular series to surround the pin 5l andthe washer 52 respectively. .Due to the above described relationship between the races 5d and 6d the balls W3 are operable to receive the' end thrusts from the cutter t@ in an outward direction or a direction away from the vertical center of the drill. In a like manner the races E@ and 6d are positioned and related so that the balls '5t assume the inward end thrusts, that is, the thrusts on the cutter 5&3 directed inwardly toward the vertical center v,ofthe drill. It is to-bounderstood, of course,

that the series of balls 5t and d@ also assume the radial thrusts on the cutter 5d. Thus the two series of balls 53 and 5d operate to transmit orassuine; the end thrusts in both. directions It is believed that the operation of Athe struc-y ture illustrated in Fig. 3 will be readily apparent from the foregoing detailed description. The cutter 5@ is supported by the spaced series oi balls t3 and 5d so that it is free to rotate with a minimum of friction. The balls 53 and 5d e' or transmit the end thrusts imposed on the cutter, relieving the head ii and the other p of the bearing from wear due to such thrusts. One series of balls 5I directly cooperates with the race 64 on the pin 5i while the other series of balls 5d, cooperates with the bushing 52 on the reduced part of the pin so that the bearing or mounting is very small or compact. The mounting is dependable and long wearing and is oper- An indented able tor support the cutter Il in the proper position for a long period of operation.

Having described only a typical preferred form and application of our invention we do not wish to be limited or restricted to the specific details set forth, but wish to reserve to ourselves any variations or modiiications that may appear to those skilled in the art or may fall within thel` scope of the following claims:

Having described our invention, we cl:

1. In a well drill, a body having spaced sup ports, a. roller cutter between the supprts and having an opening, axially spaced ball races on the interior o: the cutter, a pin carried by the supports and passing through the opening, a ball race .formed in the pin and opposing one ot the rst mentioned races, balls cooperating with the opposing races, the said opposing races being related so that a line passing through the points of contact of a ball with the races is pitched relative to the axis of they cutter whereby the balls assume the end thrusts toward one end of the cutter as well as the radial thrusts, a part on the pin, a ball race formed insaid part and opposing the'other of said rst mentioned races,

and balls cooperating with the last mentioned opposing races, the said last mentioned opposing races being related so that a line passing through the points of contact of a ball with them is pitched relative to the axis of the cutter whereby the last mentioned balls assume the end vthrusts toward the other end of the cutter as well as the radial thrusts.

2. In a well drill, a body having spaced supports, a roller cutter between the supports and having an opening, a pin carried by the supports and passing through the cutter, a shoulder on the pin forming a ball race within one end portion of the cutter, a ball race on the interior of the cutter opposing the rst mentioned race, a series of balls 'cooperating with the races to rotatably support said end portiono the cutter, the races being related so that a line passing through the points of contact of a bail with the races is pitched relative to the axis of rotation of the cutter whereby said balls assume the radial thrusts and the end thrusts toward the adjacent end o the cutter, andnieans rotatably supporting the other end portion of the cutter,`said means including a bushing on the pin and a series of balls cooperating with the bushing and the interior oi the cutter.

3. In arotary weil drill, spaced supports, a roller cutter arranged between said supports, the

`cutter having a longitudinal opening, axially spaced ball races on the interior of the cutter facing inwardly and toward the adjacent ends of the cutter, a pin carried by the supports and ex tending through said opening, a bail race on the pin opposing one of the first mentioned races, a series of balls cooperating-with the race ,on the pin and 'the said rst mentioned race. a shoulder on the pin. a bushing on the pin between said shoulder and one of said supports, a race on the bushing opposing the other rst mentioned race, and a series'of balls cooperatingwith the 4 spaced bali races on the interior of the cutter.

facing inwardly and toward the adjacent ends of the cutter, a pin carried bythe supports and extending through said opening, a ball race on 7g Cil the pin opposing one of the irst mentioned races, a series o balls cooperating with the race on the pin and the said nrst mentioned race, a shoulder on the pin, a bushing on the pin held against the adjacent support by said shoulder, a race on the bushing opposing the other nrst mentioned race, and a series of balls cooperating with the race on the bushing and the said other first inentioned race.

o. ln a rotary well drill; spaced supports, a roller cutter arranged between said supports, the cutter having a longitudinal opening, aiiiallr,r spaced ball races on the interior of the cutter facing inwardly and toward the adjacent ends of the cutter, a pin carried by the supports and extending through said opening, a haii race on the pin opposing one of the first mentioned races, a series of halls cooperating with the race on the pin and the said rst mentioned race, a shoulder entire pin, a bushing on the pin held against the adjacent support oy said shoulder, means holdm ing the hashing against rotation, a race on the bushing opposing the other first mentioned race, and a series of balls cooperating with the race on the bushing and the said other nrst mentioned 6. In a rotary well drill, spaced supports, Va roller cutter arranged between said supports, the cutter having e. longitudinal opening, axially spaced ball races on thev interior of the cutter facing inwardly and toward the adjacent ends oi' the cutter, a pin carried by the supports and extending through said opening, ,a ball race on the pin opposing one o the rst mentioned races, a series of balls cooperating with the race on the pin andthe said first mentioned race, a shoulder on the pin, a bushing on the pin held against the adjacent support by said shoulder, a tongue and groove connection between the bushing and the said adjacent support holding the bushing against rotation, a race on the bushlng'opposing the 1.Jin a rotary well drill, spaced supports, a

roller cutter arranged between said supports, the cutter having a longitudinal opening, axially spaced bali races on the interior of the cutter facing inwardly and toward the adjacent ends of the cutter, a pin carried by the supports and extending through said opening, a ball race on the on the pin a bushing on the pin held against the adjacent support by said shoulder, Welding securing the bushing to said adjacent support, a race on the bushing opposing the other first mentioned race, end a series of balls cooperating with the race on the bushing and the said other first mentioned race.

li. In a well drilling tool, a body having spaced supports, a cutter having an opening, ball races in the wall of the opening, a pin extending be tween the supports and passing through the opening, a ball race on the pin opposing one ci the rirst mentioned races, a bushing on the pin, a bali race on the bushing opposing the other of the iirst mentioned races, and halls cooperatingV with the pairs or opposing races forming the sole means for rotatably supporting the cutter.

9. in a vlell drilling tool, a body having spaced supports, a cutter having an opening, a pin extending between the supports and passing through the opening, ball bearings means in the opening rotatably supporting the cutter on the pin, said means including a bearing member on the pin having a hall race, and balls cooperating with the' hall race, and the cutter, and a weld securing said y member to one oi the supports.

lo. lin a well drilling tool, a body having spaced supports. a cutter having an opening, a pin extending between the supports and passing through the opening, ball bearing means in the opening rotatably supporting the cutter on the nin, said means including abearlng member on the pin having a hall race., and balls cooperat ina with tire ball race and the cutter, a weld securing said member to one of the supportae washer at an end ci the cutter and a Weld securing the washer to the other support.

ALFRED C. CTLAND. PIE-HMP C. EFROMSON. 

